A kagune is a ghoul's predatory organ and functions as their weapon and claws. It is usually as red as blood (the colours are varied in the anime to distinguish the kagune of each individual), flexible like the flow of water, but firm and sturdy. When released, a ghoul's physique is strengthened, they are more resilient, and their mobility heightens. A kagune is composed of Rc cells, which flow just like blood, can become as solid as teeth and can be described as "liquid muscles." The Rc cells are released from a kakuhou piercing the skin, and the released Rc cells form the kagune. The kagune are voluntary muscles as ghouls can control them whenever they want and repeatedly harden and soften them at will. Kagune size depend on the Rc cells' quality and quantity while the shape depends on the creativity and intellect of the user. Although a ghoul's healing ability is high, the healing of wounds tends to be delayed if the wounds are inflicted by a kagune. It is also evident that in order to counter a kagune in battle, one must also have a kagune, if not, at least something in relation to a kagune. Hence, ghoul investigators use kagune-based quinque as a tactical means to battle against ghouls.

UkakuAn ukaku kagune is spread out like feathers and is released from the shoulder area, it specializes in high speed attacks, most of the users seeming to have highly enhanced speed. The kagune is lightweight and can be used to deliver high-speed attacks against an adversary, the primary method of attack is crystallizing their kagune to deliver a high speed torrent of spike-like projectiles, however whilst crystallized they are much stiffer and cannot be used for short range combat; at least one ukaku-type can generate powerful lightning-like bolts, a possible rare ability. While the kagune is suited both for short-distance and long-distance attacks, short-range is considered their weakness. They may use their kagune as a shield and several are capable of shaping them into sharp blades reminiscent of a koukaku to aid in close quarters. Many ukaku-types are able to increase the flexibility of their kagune for short-range combat, though this makes it ill-suited for their distinctive long-range attacks.Ukaku's DisadvantageAltogether ukaku-type ghouls have a high chance of ending a battle quickly, releasing Rc cells depletes stamina. Thus, ukaku-type users lack endurance and are at a disadvantage if the battle drags on for a long time. Ukaku-type users can use their speed and mobility to shoot down bikaku-type users from afar. However, a koukaku-type user can suppress an ukaku-type user by successfully guarding against the ukaku-type user's attacks, leaving them vulnerable to counterattacks and exhausting the ukaku-type user in the long run.

KoukakuA koukaku kagune is released below the shoulder blade. Due to its high density of Rc cells, it is heavy and extremely robust, giving it the greatest sturdiness and making them very well suited for defense. Normally, they are generally shaped into armors or shields, but on the offense, they can be shaped like melee weapons such as drills, hammers, blades, and swords.Koukaku's DisadvantageDue to its high weight, a koukaku's speed is inferior to all other kagunes and the kagune is difficult to wield.A koukaku can fend off an ukaku onslaught using its guarding capabilities. However, a rinkaku kagune can deliver severe strikes against the slow koukaku, breaking their kagune and breaching their defenses.

RinkakuA rinkaku kagune has an appearance similar to scaled tentacles and is released at the back around the waist. A rinkaku wielder has powerful regenerative abilities and some could even survive the most critical of damage. Its peculiar appearance and structure yield a superior striking power and they excel in brute strength. Some rinkaku users are able to manipulate the shape of their kagune, such as changing its usual tentacle form into swords or claws.Rinkaku's DisadvantageThis type's regenerative power is a result of the Rc cells easily binding together. Their Rc cells are similar to liquid. However, this means that the binding force among the Rc cells are weak, therefore making the kagune very soft and easy to break. But because their Rc cells bind so easily, some rinkaku can bind their multiple tentacle-like kagune together to make a larger, stronger kagune. So far the number of tentacles that rinkaku users can create are from one to eight tentacles.A rinkaku kagune can deliver severe strikes against the slow koukaku, penetrating the kagune and breaching the koukaku's defenses. However, a rinkaku has serious problems fighting against the balanced bikaku kagune: A bikaku has comprehensively high power, allowing them to fight against the brute-force rinkaku, and the rinkaku kagune softness makes it comparatively easy for the bikaku to cut the kagune off. This disarms a rinkaku no matter how much strength it may possess, leaving the rinkaku at a disadvantage on the defensive. It has been shown that in some cases, a bikaku attack can disable a rinkaku's regeneration.

BikakuA bikaku kagune typically has a tail-like appearance and is released around the tail-bone/coccyx. It is good for medium-distance attacks and has decent offense, defense and speed. Thus, they have no notable strengths or weaknesses like the kagune based on other Rc types, meaning the kagune itself is treated as a surprise "trump card."Bikaku's DisadvantageA bikaku has better speed and durability against the brute-force, breakable rinkaku, allowing them to cut off the rinkaku's kagune. However, a bikaku will be overwhelmed by the faster ukaku-user and will lose against the ukaku's long-range attacks.The balanced characteristics makes the kagune a preferred quinque type for inexperienced investigators.

In addition to being a natural weapon for ghouls, their kagune also gives them boosts to certain stats while active.

Ukaku-type ghouls gain a +2 to Speed while active.

Koukaku-type ghouls gain +2 to Durability while active.

Rinkaku-type ghouls gain +2 to Strength while active.

Bikaku-type ghouls, being the most balanced, gain +1 to all three stats while active.

Each kagune also gets 1 special ability while active. These can include anything from increased regeneration to the ability to detach themselves and create traps. As the strength, quality, and quantity of a ghoul's kagune is based on their number of kakahou, there is a fairly easy way to figure out how many one has:

C Rated Ghouls have only one kakahou.B Rated Ghouls have two kakahou, and thus can create two of their kagune.A Rated Ghouls have three kakahou.S- Rated Ghouls have four kakahou, and are thus able to generate four kagune at will.S+ Rated Ghouls have five kakahou in total.SS Rated Ghouls have six of the predatory organs.SSS Rated ghouls have eight kakahou, making them extremely powerful.

If a ghoul loses or damages a kakahou in a fight, you must do 500 words of recovery before you are able to use it again. Investigators looking to harvest one of these organs to create a quinque need only one, so please keep that in mind. We don't need to deal with any kakahou farms that the plot doesn't call for, or anyone's character dying because of this.